Railway traffic controlling apparatus



Jan. 9, 1945., c. w. FAILOR RAILWAY TRAFFIC CONTROLLING APPARATUS Filed Sept. 16, 1943 s Sheets-Sheet 1 W n wmr m ww m m Q A Q .s fiQww ww m \NQMNQQWN B L \N I A, MN L L Kw L \N %N E m \N %N A l. xv v Jan. 9, 1945. c. w. FAILOR .RAILWAY TRAFFIC CONTROL-LING APPARATUS Filed Sept.- 16, 1943 3 Sheets-Sheet 2 INVENTOR Clzafiler Z11 FJZZOP. BY am HIS ATTORNEY Patented Jan. 9, 1945 UNITED STATES NPATENTT O'F 'FICEf 2,366,776 RAILWAY TRAFFIC CONTROLLING l CharlesW. Failor, ForestHillsQ Pa.j, assignor to H i TheUnionSwitch & Signal. Company, Swiss i vale, 2a., a corporation of'Pennsylvania l 16, 1943, Serial No. 502,586:

. ironims. =--(c1..24c--2s)1 Application September My invention relates to railway traffic controlling apparatus, and particularly to trafliclocking apparatus. 7 q

When trafllc is operated in either direction over a railway track extending between two spaced locations traffic locking apparatus may be prothe track stretch is vacant and controllinglamps which indicate to the operatorsat the ends ofthe stretch whether or not the controlled stretch is vided which includes a trafficlocking circuit controlled jointly by two operators, one at each end of the stretch of railwaygtrack. Such tratfic lock- -ingcircuit is arranged to prevent themanipulation of traffic governing-signalleversor units for changing thedirectionpf traific on the stretch of track betweensuchtwo spaced locations while the stretch is occupied, or while a signahis displayed for a train to proceed into-- such stretch:

A traffic locking circuit'lsimilar to-that shown in this application is "shown in Letters Patent 'of'the United States No.2,354,023, issuedJ'uly 18, 1944,

to C. D. Ihrig. i

An object of this invention is to provide improved apparatus of the type described which is arranged so that whentraffic is established for either direction it can bechanged only by the "Injthe drawings' Figs; 1A and 13; when occupied.

A furtherobject of the invention is to-provide an improved traffic locking circuit.

Other objects of the invention and features of novelty will be apparent from the following 'del scription taken inf connection with the accome panying drawings. 1 p .jI shall describe one form of traflic locking apparatus embodying myinvention, together with two modifications thereof whichlmay employ and shall then point out the novelfeaturesthereof in claims.

placed together with Fig. lB-at the'right, forma diagram showinga Y stretch of railwaytrack equipped with trafilc locking apparatus embodying my invention;

. Fig. 2 is a fragmentary view showing system of Figs. 1A and 1B maybe modified to maintain the supply of energy to the line circuit operator at the existing entrance endof. the

stretch. l A further object of the invention is to provide a system of the typedescribedwhich is arranged so that once reversal of the established direction of trafiic is initiated; functioning f the equipment i incomplete the reversal oftraffic cannot be disturbed by the operatorateither endof the single track stretch;

Another object of the. invention is" to provide traflic' locking means governed over-a line circuit controlled by" the traclc circuit" apparatus of: the

controlled stretch, thetraffiolooking: means governing connection 'ofthebra/olcoircuitapparatus t with the rails of the track sections in thecontrolled-Stretch:

l A further object of the invention is to providetrafll'o locking apparatus oi itm type" described which employs stick" polar trailic locking relays which are energized overa line-circuit, while the relays governing theline' circuit are slow acting with the resultthat ona change in the polarity of the" energysupplied to-the line circuit the re- 1 lays governing: the line circuit maintain. the line circuit for: a period: long enough-t0 insure that the 3 contacts oi the 'polar" relays will move from one position to the other before the line circuit is interrupted.

Another object of the invention: is to provide trafficloclring apparatusofthe type described and stretch is not required.

after a signal controlling entrance of trains into the single track stretch has beencaused toprovide a permissive indication, and thus continue energizaticn off the block indication relays until a train enters the single trackstretch, and

Fig. 315 a fragmentary view showing how-the system of Figs. 1A and 1B may be modifiedif the l meansfor indicating occupancy of the single track In practicing my invention 1- provide a. stick {polar traffic lockingrelay at eachend of the protected. stretch and also attheends of the track Ysections in the stretch, and-I provide-a line circuit over whichenergy of one polarity or the other i may be suppliedto the trafilc locking relays in series, The equipment at each end of the line circuit is arranged so that when traffic is established for either direction-the equipmentat the I exit end o-f the stretch establishes a connection between the line wires, and this connection. canincorporating indication relays energized by current supplied over the trafiic locking circuit when i 5 not be interrupt'ed' by any manipulationof the i 4 equipment by the operator at that location. The

, "equipment at the entrance end ofI the stretch is arranged sothat theoperatoratthatpoint may cause to be supplied to the line circuit energy of apolarity effective to cause thecontacts of. the polar traffic locking relays to move from one position tothe other. The stick polar trailicslocking relays govern control'relayswhich reversibly connect the track circuittapparatus with the rails of the track sections, while the track circuit, ap-

paratus controls the linecircuitto prevent supply how the of energy over the line circuit when the protected stretch is occupied. The relays governing the line circuit are slow enough in releasing so that on a. change in the polarity of the energy supplied to the line circuit, the line circuit will be maintained for a period long enough to insure that all of the trafiic locking relays will respond to the energy supplied to the line circuit before the line circuit is interrupted. a

Neutral block indication relays may be connected in series with the line circuit at each end thereof so as to be energized by current supplied over the line circuit .to provide an indication whether or not the protected-stretch is occupied. When these relays are employed the equipment at the ends of the stretch is arranged so that energy of the polarity effective to maintain the established direction of trafiic is supplied to the line circuit at the entrance end of the stretch until it is desired to reverse the direction of trafiic, at which time the polarity of the energy supplied to the line circuit is reversed.

Similar reference characters refer to similar parts in each of the three views.

Referring to Figs. 1A and 1B of the drawings there is shown therein a stretch of railway track having track rails l and 2 over which traffic may move in either direction. Adjacent the left-hand or west end of the single track stretch is a passing siding or branch track WPS, and adjacent the right-hand or east end of the single track stretch is a passing siding or branch track EPS.

The passing sidings or branch tracks are connected with the main track by suitable track switches.

Although this system is illustrated in connec-- tion with a single track stretch joining two passing sidings or branch tracks, the system is not limited to use in situations of this kind and may be employed wherever traflic may move in either direction between two points,. but only in one direction at one time.

l The track rails I and 2 are divided by insulated joints 3 into track sections for signaling purposes. As shown there is a, section 41 which includes the switch 4W connecting the passing siding WPS with the main track, and a section 1T which includes the switch 1W connecting the passing siding EPS with the main track. The single track stretch between sections AT and IT is divided into sections ST and GT, but it is contemplated that the single track stretch may include a larger number of track sections.

' The track sections ST and BT of the single track stretch are provided with track circuit apparatus which may be of any appropriate type. As shown the track circuit equipment for these section's-is of the coded type and makes use of coded energy of two code frequencies, while the trafiic locking relays reversibly connect the track circuit ap-.

paratus with the section rails to condition the track circuits for movement of traffic through the single track portion in the selected direction.

The track sections 4T and 1T, which include I the track switches AW and 7W, are provided with suitable track circuit apparatus, and as shown these track circuits are of the steady energy type v and each includes a track relay which is supplied with energy from a track battery over-the section rails.

Movement of trafi'lc along the main track from left to right is governed by signals E8 and, SES, while movement of trafiic from right to left along the main track is governed by signals GWS and 5W5. Movement of trafi'ic between the main wayside signals of this type and any appropriate type of wayside signal may be employed.

Similarly, this trafiic locking means is not limited to use in track stretches in which movement of trailic is governed by wayside signals, and is adapted for use in track stretches in which movement of traffic is controlled by cab signals, either alone or in conjunction with wayside signals.

The polarized trafiic locking relays FR, which control the direction of traffic in the single track stretch, are energized in series over a line circuit extending between the passing sidings. Atraffic locking relay is located at each end of the single track-stretch, and, in addition, a traffic locking relay is located at the junction between track sections in the single track stretch. In the system shown in the drawings, a traffic locking relay [PR is located at the west end of the single track stretch, a relay 2FR is located at the adjoining ends of sections ET and ST, and a relay SFR is located at the east end of the single track stretch.

Each of the trafiic locking relays has associated therewith a westbound control relay WFPR, and an eastbound control relay EFPR, while the equipment at each end of the single track stretch includes a block indication relay BPR, a directional stick relay SR, a push button stick relay PBSR, a repeater relay FCR, traflic direction lamps E and W, a block occupancy lamp M, a signal control or traffic lever K, a push button PB, and a line battery LB.

The signal levers K, the lamps F, W, and M,

and the push buttons PB at the ends of the single track stretch may be mounted in interlocking towers located at the ends of the single track stretch, while the levers K and push buttons PB may be operated by attendants in these towers.

. able source of direct current, such as a storage battery, not shown, the terminals of which are designated B and C in the drawings.

The signals 5E8 and BWS controlling movement of trains across the switches are governed -by signal control relays 5RHR and ELI-1R, re-

spectively, which are governed by the trafiic locking relays, the track relay of the associated detector section, and the traffic levers, while each of these relays may also be controlled in the manner well known in the art by the position of the associated track switch and by traffic conditions in the'vicinity of the switch. One means for controlling the relays SRHIR and BLHR is shown in Letters Patent of the United States No. 2,093,170 to Ronald A. McCann.

In most instances the relay contacts are shown directly underthe relay winding, but in some cases in order to simplify the drawings relay contacts are shown separated from the relay 20 and 2|.

.stretch that the direction of relays 2H and ZJ are picked up energy is supplied over front contact 78 of relay 2EFPR, front contact 19 of relay 2H, and front contact 80 of relay N to the green or clear lamp G of signalGES.

As relay 2H is picked up its,contact 82 establishes the circuit controlled by a contact of code transmitter lii flCT for supplyingenergy from the track battery 2TB to the rails of section T. This energy feeds to trackrelay SETR and operates it so that energy is supplied through the associated decoding transformer to relay 5EH and through a resonant rectifier unit IBUDU to relay SEJ. Accordingly relays 5EI-I and 5EJ are picked up, but at this time relay ERHR is released so energy is supplied over back contact 84 of relay BRHR to the red or stop lamp R of signal 5ES.

At this time energy is supplied over back contact 85 of relay ZWFPR to the red lamp R of signal 5WS, while energy is supplied over back contact 86 of relay SLHR to the red lamp R of signal 6W8.

As relay ZWFPRis released its contact 51 interrupts the pick-up and stick circuits for relay SPBSR so that this relay will remain released even though the push button SPB should be depressed. Accordingly, contacts 3| and 34 of relay 3PBSR. maintain the connection traced above between line wires 23 and 2| so that energy of normal polarity for battery ILB may be supplied over the line wires to the relays FR and BRP, while contacts of relay 3PBSR cannot be picked up to establish the circuit to supply energy of reverse polarity from battery 3LB to If the operator at the west end of the single track stretch wishes to clear the signal 5E8 to permit an eastbound train to enter the single track stretch he may do so by moving the control lever IK from its position N to its position R. On this movement of the lever, the lever contact 8'! establishes the circuit including front contact 83 of track relay 4TB and front contact 88 of relay IEFPR for supplying energy to relay SRHR, i

so that contact 84 of relay ERHR is picked up and interrupts the circuit of the red lamp R of signal 5ES and establishes the circuit including front contact 89 of relay 5EH and front contact 90 of relay 5EJ for supplying energy to the green lamp G of signal 5E8. Accordingly, signal 5ES displays a proceed indication and authorizes an eastbound train to enter the single track stretch.

When the lever lK is moved to its right-hand position contact 93 interrupts the pick-up circuit 4 for relay ESR, while contact l5 interrupts the stick circuit for relay ESR. Accordingly, relay ESR releases and its contact I4 additionally interrupts the stick circuit of relay ESR, While its contacts l8 and i9 interrupt the circuit of the line wires 20 and 2! so that the block indication relays IBPR and 3BPR release and interrupt the circuits of the lamps IM and 3M. These lamps, therefore, are extinguished and indicate to the operators at both ends of the single track trafiic cannot be changed. 7

On release of relay ESR and resultant inter- .ruption of the circuit of line wires 20 and 2|. the relays IFR, 2FR and 3FR are deenergized, but

the operating characteristics of these relays are such that their contacts remain in the position which they already occupy. Accordingly, the circuits of relays EFPR and the circuit of relay IEFCR are maintained and these relays mainthe line wires tain the track circuit apparatus in the condition described in detail above.

When a train moving in the normal direction of traffi-c enters section 4T track relay 4TB. releases and its contact 83 interrupts the circuit of relay BRHR so that contact 84 of relay SRHR releases and causes si-gna1 5E5 to display its red -or stop indication. In addition, contact 94 of vent the display of a permissive indication by I signal 5E8, while contacts 24 and 25 of relay.

5EH additionally interrupt the circuit of the line Wires 20 and 2| and thus prevent a change in the established direction of traflic.

When the train advances into section ET the track relay ZTR is shunted and ceases to follow code so that relays 2H and 2J release and cause signal BES to display its stop indication, while contact 82 of relay 2H changes the energy sup plied from battery 2TB to the rails of section 5T from 180 to '75 code frequency.

When the train advances into section 1T track relay ITR releases and its contact. 95 interrupts the pick-up circuit for relay WSR but this relay remains energized by current supplied over are closed to permit. energy to be supplied to relays SRHR and ESR, respectively. ,Under normal conditions when an eastbound train accepts the proceed indication provided by signal 5E8 as a result of movement of lever IK to its position R and. enters the single track stretch, the operator will return the lever l K to its normal or intermediate position N.

Accordingly, lever contact 81 interrupts the.

circuit of relay 5RHR so that on picking up of relay 4TB. energy will not be supplied to relay BRHR and its contact 84 remains released and maintains the display of the stop indication by signalEES.

If the lever IK is left in its position R so that lever contact 81 is closed energy will be supplied to relay 5RHR and its contact 84 will be picked up to permit signal 5ES to provide a permissive indication. If the lever IK is left'in its position R lever contact 93 will interrupt the pickup circuit of relay ESR so that on picking up of relay 4TR relay ESR will remain released and will interrupt the circuit of line wires 20 and 2i so that the established direction of trafiic cannot be changed.

If the lever IK is returned to its normal po sition N energy will be supplied to relay ESR over I lever contact 93 and front contact 94 of relay 4TB when section 4T is vacated. Accordingly, relay ESR picks up and its contact M establishes a stick circuit for the relay, while contacts I8 and I9 which control the circuit of line wires 20 and 2| are closed.

When the train vacates section 5T coded energy feeds to track relay SETR and operates it 1 to be l 2:33am so "that relay 3m: picks up and "its cdntats n and25 are losed'top'ermit "the circuit of the line WiresMancMI tobe established. 3 i i When the train vacates section "BT "coded en-- ergy feeds to relay ZTR-andoperates it so'that energy is supplie'ti to relay 21-1 "with the result that "signal GES displays its caution indication,

while contact 82 of relay 2H changes the energy supplied to the rails of section 5T fromfib to 180 codetfrequency, and contacts 21 and 3-9'of relay "2Hfare closed to permit the circuit of line wir'es 2'0 and-2| to be established.

Whenthe fsignal 'control -l'ever IK'is returned to itsinterm'etiiateornormal position N andse'ction 4Tis vacated; contact 93 of thesi gnal lever long as either se'cuon ST "or a r is occupied the circuit of i the 1i'ne"wires 2D and 2| is "interrupted and. the Ttral m'c locking frelaysflFR and the indicationr'elay fBPR are deenergi'zed.

When thetramaavances tar erroughtoivacate are picked "up, the circuit of "line wires 20 and ZIfis complete and energy rr'om theb'attery-ILB iS 'sllfiplieii over the line wires '20 'and '21 Ito energize fithe tfafiic locking ireIays FR and the inflirtation relays 'BPR'in series. Accordingly, :the

contacts of,relays IBPR and -3BPR .pic'k up and establish the circuits (if-'thelindication lamps VIM andiiM, respectiv1y,1to indicate to the operators at both erfds of the sin gletracks'tretch that the directioho'f'traffic in'the-jsinletrack stretch may berleversedif desired. I

It is to be observed that thecircuit of the line wires "20 and 2t is complete as soon as,-section 'BIis vacated. This. permits traific .to be reversed while a ttrainis in section 'TT and makes it un necessary to wait for seotion 'lT to be vacated.

When the train :vac-ates section J'Tftrack .relay picks tip and its contact til-changes m energy supplied-to section fiT from 75-to 1'80 code frequency so thatrelay 2mi$pemted at a irate such t wicked 119350 m y signal 5E3 -dip1ays-if reen Onclfiflindioation. l oher ation wseqmpmmmc W established w rection o'f m "rmssyamsmatge ot at whenthesinle track stretch unoc'ciipied and the signals goyer-ni'n'g entrance df ftrairis into the single tr acl; stretch "are dis laying their sto inhidationsthe as tot'cause relay 2J1 as: -we11 as relay -2H i as lbng ss thestretch is coniiittcriedtor eastbound at the endo'f the-single trackstretch atwhich trains are-permitted to enter the stretch must depress the push -button "at his location, thereby indicating thathe is willing to-surrender control of the' siIrg'le-trak stretch. "-Wh'en tra'lficis to be ehanged from eastbound to westbound the push button lPB at thewest V end=of the stretch is depressed; thereby establishing "a mick-111p eircuiti'for relay IPBSR. F This circuit includes'front-contact 10 of relay IEFPR,

front-contact M Korma-y IBPR andlpush button ses wuuewnen-reis Nessa picks up its C ntact H -=establishes a-stickcircuit to keep the relay energized loirg' es relay \IEFFPR is energized.

The-'stic'k'cireuitfwhich relay iP-BSR establishes for itself when i it is picked up insures that once the=push button IPBFis tiepres'sedto pick uprela'y lPBSR Hnd initiate reversal O'f thexestablished direction 'of tr afii'cflthe relay IPBSR, w n remain picked-up until'thi s: reversal of trafiic is complet'ed. In addition tvhen relay -I'PBSR' picks up its c one tact =2 establishes a stitzk circuit for i'elaiy ESR including '--its= own-front contact I 4 "to insure that l relay IESR will remain picked up and maintain 1 thecircuit o t the line Wiresill -and"2|.

and H interrupt th'e previously traced circuit for ecmne cting the 'b mew 1 BB w ith thewires {2 0 and fifland eomie't thisbatterytb thSe wires with the positive terminalof the battery connected to wire lfl so thahthere' is a reversal-inthe@olarity o-flthe energy'suppl-ied' to thelin'evtires. t

*On this ch'ange in 'the polarity of the energy tactS- o'f the trame leakin relay-s 'IFR, and

nuns so that the circuits 'of the rlays E FPR are interrupted, while circuits are establishedi or the relaysWFPR"aifteritherelays EFPRrelease. "The directionkoftfalfii'c in the single track stretch may When the single track stretch is vacant, the

signalcc'ntrdiuever IK isl'n its'norm'al position,

' contacts of .reIaysWEF'BR andEsR. "The connecti'on's "from the battery "to .theline wire era-arran'ged "'so that "thefpo'sitivef terrriin'a'l of the :batteryis connected to l-inefwi're 21, while energy remysFR causes their-contacts to'occupy their left-hand ornnormal positions i r Aspointecl out 'a'bovefatthis time relay SPBSR tainsconnectionfbetween Wires 3 2'0 and Z I to permit erier'gy from battery I liB-ftojbe supplied over the fine wires,'=whilerelay- =3PBSR-"pi'events supply or energy from hatter? 3m; to the 'line wires '76 I relays "EFPR,

oirc-utt for 'supp'lying energy torelay *IWFPR ini eludes reverse polareontactfi"of relay FER. and

back con L-tat' l1 '0": relay "IEFPRf-While the circuit for supplyirigfiehergy ytoxrelay ZWFPR includes reverse p'o'lar suntan-t "1 9 of relay jZFR and back contact can o'frlayl EFPR. The circuit "for supplyingfienergy toirl'ay iwFPR includes reverse V polartcoritac t 520f relay itIFR"and'back contact 91 of relayBEFPR. When the relays W'FPR pick up they interrupt 'the circuits ofithe associated released.

onunease-errawhmnand pickifisup 'f relay KWV'FPR the connection "between "line wires Hand 2 I -estahlishedhy front'contact 3-3 "of jrlay interrupted, 'vrhile wire 2!) is connected over back tact 3'! {6t rIaWSPEB SRKand front contact 32 or relay 3WFPRto the positive terminal of battery 3L3. 'lichorciingly,-' energy is-"supplied from the battery 3133305131'1'6 "wires *20 2|, "While the polarity is: t-his energ-yus such thavenergy from the =ba' ttery-3EB assists the energy from" battery 1 in-maintaiining the =contacts of "the traffic lockingrl-ays'FR'in their -r everse{positions F01 1 movement or the contacts o f the tram locking relay "and resultant release of the eastbound"cofitrol'rl yfiEFPR thecircuit of'line wires lu anh fi plks lipi I-isl titterrupted hitele -awn The control relays EEFPR, and RWFPR are of a. type which are slow to release so that on movement of the contacts of the trafiic. locking relay 3FR and resultant interruption of the supply of energy to a control relay, the contacts of the control relay remainv picked up for a short period and cause the circuit of the line wires 20 and 2| to be maintained so that energy continues to be supplied over these wires to the relays FR to insure that the contacts of all of the relays FR will completetheir movement from one position to the other before the supply of energy to the traffic locking relays is interrupted.

On movement of the contacts of relay I FR to their reverse. position contact 51 interrupts the circuit of relay I EFCR, while the circuit of this relay is additionally interrupted by contact 58 of relay IEFCPR when that relay releases. On release of relay IEFCR its contacts Gil and GI interrupt the circuit of track relay EETR. and establish the circuit for supplying coded energy from the battery ETB to the rails of section 5T. Accordingly, relay SETH ceases to follow code and relays 5EH and 5EJ release. The relay EEH is of a type the contacts of which are slow to release so that contacts 24 and 25 maintain the circuit of the line wires and M for a period subsequent to movement of contact 45 ,of relay IFR so that energy continues to be supp-lied over these wiresto the traffic locking relays FR to insure that the contacts of all of the relays FR will complete their movement from one position to the other.

- On release of the relay IEFP R its contact I0 interrupts the pick-up and stickcircuits for relay .IPBSR so that its contacts release and contacts It and Il interrupt the supply of energy from the battery ILB to the-line wires 20 and 2| and establish a connection between these wires which is traced from wire 20 over back contact I 6 of relay asea'zze battery 2TB from the railsof section 5T. In 'addition, on release of relay" ZEFPR its contact I8 prevents the supply of energy to the yellow and green lamps of signal BES and establishes the circuit of the red lamp R of that signal;

IPBSR front contact 22 of relay IWFPR, back contact 33 of relay IEFPR, andback contact I! ofrelay IPBSR to wire 2!. Accordingly, energy supplied from battery 3LB to the wires 2!! and 2| .ilows over the circuit provided by these Wires and energizes the relays FR tomaintain their contacts in their reverse positions,--while the contacts of relays I BER and 3BPR are picked up and establish the circuits of the indicationlamps IM and 3M to indicate that the single track stretch is unoccupied.

On release of relay I,PBSRits contact I2 interrupts one stick circuit for relay ESR, but this relay continues to be energized by current sup= pliedover its pick-up and stick circuits controlled by contacts of lever 5K, and over the stick circuit established by front contact I02 of relay IWFPR. .The relay ESR, therefore, remains picked up and its contacts I6 and I! maintain the circuit of the line wires 20 and 2|. The stick circuit for relay ESR established by contact I02 of relay IWFPR on picking up of relay IWFPB prevents release of the relay ESR if the signal control lever IK is moved to its position R while the single track stretch is conditioned for westbound trafiic.

, On picking up of relay IWFPR its front contacts I00 and Illl are closed and maintain the circuit of line wires 20 and 2| after release of contacts 24 and 25 of relay 5EH. If the relay EEH releases before the relay IWFPR picks up the circuit of the line wires 20and 2| will be momentarily interrupted, but this interruption of the circuit of these wires is without effect other'than momentary release of the relays BPR since the polar contacts of relays FR will have already lamps W at both ends On picking up of relay 2WFPR its contacts I04 and I05 connect the track relay 2TB across the rails of section 5T so that the relay ZTR is operated by energy supplied from battery SETB at the west end of the section, while contact of relay ZWFPR interrupts one circuit for supplyingenorgy to the red lamp R of signal SWSand establishes the circuit controlled by contacts of relays 2H and 2J for supplying energy to the lamps of I signal 5W3. In addition, on picking up of relay 2WFPR itscontacts I08 and I09 connect the battery 2TB across the rails of section 6T so that coded energy is sup-plied to section 6T at the west end of the section. c When relay 3WFPR picks up its contact III) establishes the circuit of the associated lamp W, while the circuit of the lamp E is interrupted by contact 56 of relay 3EFPR. Accordingly, the of the single track stretch are lighted to indicate that'the stretch is conditioned for westbound traffic.

At this time contact I I2 of relay 3WFPR is closed to permit energy to be supplied to relay ISLHR. on movement of lever 3K to its position L.

In addition, at this time energy is supplied over reverse polar contact 69 of relay 3FR and front contact 10 of relay 3WFCR. Accordingly, contacts i2 and 13 of relay 3WFCR. are picked up to cut off the supply of energy from battery GETB to the rails of section ET, and to connect the relay BWTR across the rails of section 6T so that it is operated by energy supplied from-battery 2TB to the section rails; As a result of operation of relay GWTR relay GWH picks up, while relay 6WJ may also pick up. However as long as signal control lever 3K is in its intermediate position N the contact I I4 interrupts the circuit of relay 6LHR and its contact 86 is released and establishes the circuit of the red lamp R of signal BWS to prevent a westbound train from entering the single track stretch.

When relay 6WH picks up its contacts I24 and I25 are closed ,to permit energy to be supplied over the line wires 20 and 2|. In the period from release of the contacts of relay ,3EFPR until picking up of relay EWH the circuit of wires 20 and 2! is interrupted, but this is without consequence except for release of relays IBPR and 3BPR since the contacts of all of the traflic locking relays FR will complete their movement be fore the circuit of the line wires 26 and 2I isv contact H. Accordingly, the contacts tlliandt! of relay WSR are picked up andmaintain the circuit of line wires and 2| so that energy from the battery 3MB isflsuppliedto the trail-"1c locking relays ER and to the indication relays BPR. i I i i it t The circuit tor supplying energy from the battery 3LB is traced from tthevpositive terminal of the battery over front contact 32 of relay contact 30 of relay WSR, wire '21, windings of relays 3BPR "and 3m, front contact I "of relay and enters section 1;Itrackrelay lTI-R releases and its contact I I9 interrupts the circuit or rera y GLHR so that its contact 86 releases and establishes the circuit of the red lamp R otsi ghal GWS. In addition, contact 95 of relay TIR-inten rupts the pick-up circuit of relay WSR to unsure that it willremain released and interrupt the eircuit of line wires 20 and 2! and therebyl'prei/ent a change in the established direction oftrafflc When the train enters section B'Ithe track relay EW'IR ceases to follow code and relay GWH releases and its contacts I24 and IZS interrupt BWH, front contact 211 of relay 2H, winding of relay 2m, front contact 24 of relayQSEH, wind ings ioftre'l-ays IFR and IBPR, front contact 139 of relay ESR, back contact 11 of relay lP-BSR, back conta'ct 23 of relay IEF PR, iro'nt contact 22 of relay IWFPR; back contact 16 of relay IPBSR, front contact 48 of relay ESE, wire 20, front-contact $25 or relay BEE-I, front contact 39 of relay Z'I-I, front contact +24 or rela twn, front a contact '35 of relay WSR, back contact 34 of relay 3PBSR, and back contact-33 "of relay BEFZPR to l the negative terminal of the "battery. i

Asrelay IEEPR is released its contact l t ih ter rupts rthe piok 'up andsti'ck circuits :for relay lPBSR "and it remains released so that its contacts [i6 and ll maintain the connection between wires '20 and '21 through rt'rcnt contact 22 of relay IWFPR and back contact 23 of relay lEF-PR.

lithe operator at the east end of the single track Stretch wishes to cause signal 6W8 to dis play-a proceedindicatiom and "thus authors-Zea westbound train to enter the single tracksti'etch;

he may do so by moving the lever 3K to its positionlL so that lever "contact, l establishes the circuit including front contact N9 of track. relay "lTRand front contact H2 of relay 3WFPR for supplying energy to the relay GLHR; Accordinterrupts one circuit 'fO-r suppl ing energy to the l ingly, contact 86 of relay ELI-IR is picked up and red lamp R of signal 'BWS and establishes the circuit controlled by contacts of reIays SWH and BWJ :forvsupplyin'g energy to the lamps of signal 5W3. l At this time sections 51 and ET are 'vau cant and relay GWTR will be operated at the 189 code rate so relays BWHand BWJ are both picked up and on picking up for relay SLHR energy is suppliedwover front contact 86 of relay BLHR, front contact 120 of relay SWH, and front con tact I21 of relay ISWJ to the green lamp G of signal iWSn The signal BWS,thereforedisplays its clear indication to authorize a westbound train to'ent'erthe single track stretch.

- 'When the lever 3K is moved to its position L contact H6 interrupts the pick-up circuit for relay WSR, while contact 1 I5 interrupts'the "stick circuit for relay WSR and its contacts release so that contact It additionally interrupts the relay stick circuit, and contacts 30 "and interrupt the circuit of linewires 20 and 2! to thereby cut off the supply of energy from battery 3LB to these Wiress As a resultr'elays IBPR and 3BPR release andinterrupt the circuits of theclamps 1M and 3M and thus indicate to tHQ'QDGIQJbOIS "at both ends of the single track stretch that the direction of trafllc in thesingle track stretch cannot be changed;

At this time the relays FR are deenergi'zed but i a the operating characteristics or the relays are such that their contacts remain in their reverse positions and thus maintain the circuits of relays to thereb condition the single track streteh'icrwestbound tramc.

the circuit of the line wires 20 andfZl aild thus l prevent a change in the established direction of trailic. When thetrain advances into section 5T, traclrrelay 2TB is shunted and relay =2H res leases and its contact I 2] establishes the circuit of the red lamp R or signal 5W3, while its com tact 82 changes the energy supplied to section 61 from 180130 code frequency. In addition,

contacts ZIand 3901? relay 2H interrupt the cire cult of line wires 20 and 2|,

When n the train advancesi'nto section 4T track relay 4TB releases and its contact! interrupts the mak up circuit of relay ESR, but this rel'ay is maintained energized :by current supplied over its stick circuit which includes its own front con tact It and front contact l I12 of relay lWFPR. In addition, :contact 432 'of "relay 4TB changes the energyisupplied to section 51 from 180 to 75 code frequency. y t i p l l As shown selection between 75 and. 180 code energy supplied to the west end of section 51 is controlled by track relay 4TB, but the fre quency of this energy may also becontrclled by trafiic in the section l in advance and by the position of the switch 4W and the aspect dis played by the westbound signal associated with switch 4W. i

When thetrain vacates section IT track 'lTR picks up and if signal control leVer BK has been restored to its center or normal position N, energy will be supplied to relay WSR over its pick-up circuit whichincludes lever contact I I6 and front contact of relay 1TB. Accordingly, the contacts of relay WSR. pick up and contacts 30 and 35'are closed to permit energy to be supplied over wiresZlLand 2!. i

When track relay 1TB, picks up its contact H9 is closed to permit energy to be supplied to relay ELI-IR, butiflever 3K has been returned :to itsnojrinal position, as is customaryQthe lever contact H4 will interrupt the circuit of relay GLHR and its contact 86 remains released and fm'aintains the display or the stop indicatiohhy signal GWS. i

In addition when lever 3K is returned to "its normal position N and track relay 'ITR, picks up energy is supplied to relay WSR over it's pick-up circuit which includes levercontact llli'and track relay contact 95 so relay WSR'pick's up.

When the train vacates section 5T coded energy feeds totrack relay SWTR and operates it so that relay BWH is picked up and its contacts I2! and I25 are closed toperlnit energy to be sup plied over line wires 20 and 2|. j

When the train vacates section 51' coded energy reeds tot-lack relay 2TH and operates it so that relay 2H picks up with the result thatfits contact 121 establishes the circuit including back contact I28 of-relay U for supplying energy to the yellow lamp Y of signal 5W8, while contact 82 changes the energy supplied to section 51' stem '75 to code frequency. In addition, com

When a westbound train accepts signal relay tacts 21 and 39 of relay 2H are closed to permit energy to be supplied over line wires 26 and 2|.

The circuit of the line wires 20 and 2| is now complete and energy from battery 3LB is supplied over the wires 20 and 2| to the relays FR and BPR over the circuit traced above. Accordingly, the relays IBPR and 3BPR are picked up and cause lamps IM and 3M to be lighted to indicate that trafiic in the single track stretch may be reversed if desired.

In addition, contact I33 of relay 3BPR is closed so that energy may be supplied to relay 3PBSR over its stick circuit on closing of the push but- Operation of equipment to change from westbound to eastbound traffic The equipment is arranged so that the direction of traffic in the single track stretch may be changed from westbound to eastbound if the single track stretch is unoccupied and the control lever 3K is in its normal position N. Under these conditions energy from battery 3LB is supplied to the line wires 20 and 2|, while the circuit connections are such that the positiveterminal of the battery is connected to wire 2|. Energy supplied from the battery 3LB over the line wires 20 and 2| energizes the relays FR and BPR. As the contact I30 of relay 3BPR is picked up the pick-up circuit of relay 3PBSR may be established when the push button 3PB is depressed.

At this time the pick-up and stick circuits for relay |PBSR are interrupted by contact Iii of relay IEFPR so that relay IPBSR is certain to remain released even if the should be depressed.

In order to change from westbound to eastbound traffic the operator at the. east end of the stretch depresses the push button 3PB, thereby establishing the pick-up circuit for relay 3PBSR and its contacts pick up and its contact I33 establishes a stick circuit to maintain the relay picked up as long as relay 3WFPR is energized. V

On picking up of relay 3PBSR its contact 34 transfers connection of wire 20 from the negative to the positive terminal of the battery 3LB, while contact 3| transfers connection of wire 2| from the positive to the negative terminal of the battery 3LB. Accordingly, there is a change in the polarity of the energy supplied to line wires 28 and 2| with the result that the contacts of the trafiic locking relays FR shift from their reverse to their normal positions to interrupt the circuits of the westbound control relays WFPR and to establish the circuits of the eastbound control relays EFPR.

As a result of release of relays WFPR and picking up of relays EFPR energy is supplied from battery |LB to the line wires 20 and 2| while the supply of energy from the battery 3LB.to the line wires is cutoff, and connection is established between the lines wires at the east end of the stretch. In addition, the track circuit and other apparatus is conditioned for eastbound trafiic push button IPB while the equipment assumes the condition originally described.

This system is arranged so that irregular manipulation by the operators of the equipment at the ends of the single track stretch cannot create a condition in which trafiic isestablished for one direction in one part of the track stretch and in the opposite direction in the other part of the track stretch. If such a situation were to occur the circuit of line wires 20 and 2| might be interrupted and it would be impossible to supply energy over the circuit of these wires to the trafiic locking relays FR to bring them into correspondence. This would make it necessay to have a maintainer inspect all of the traffic locking relays and place their contacts in correspondence. When the equipment is conditioned for eastbound trafiic energy is supplied from battery |LB to the line wires 20 and 2| over back contacts of relay IPBSR, while connection is established between wires 20 and 2| over back contacts of relay 3PBSR; The pick-up and stick circuits of relay 3PBSR are interrupted by contact 51 of relay 3WFPR so that closing of push button 3PB is without efiect. The relay WSR is energized by current supplied over the stick circuit which includes front contact |3 of relay 3EFPR and front contact I0 of relay WSR so that no movement of the lever 3K can cause release of relay WSR with resultant interruption of the line circuit. Accordingly, when the stretch is conditioned for eastbound tranic, no operation of the push button 3PB or lever 3K at the east end of the stretch can disturb the established direction of traflic.

When the direction of traffic is to be reversed push button lPB is depressed and relay IPBSR picks up and reverses the connections from battery |LB to the line wires 20 and 2|. When relay IPBSR, picks up it establishes a stick circuit to maintain itself energized as long as relay IEFPR is picked up, while it also establishes a stick circuit for relay ESR. Accordingly, once the push button IPB has been depressed to pick up relay IPBSR, release of the push button or movement of the control lever |K will not affect either relay |PBSR or relay ESR, and the contacts of these relays will remain picked up and maintain the supply of energy from battery LB to the wires 20 and 2| of the polarity effective to move the contacts of the traflic locking relays FR to their re-. verse position;

As explained above, the relays governing the line wires 20 and 2| are sufiiciently slow in releasing to maintain the circuit of the wires 20 and 2| for a period, and thus permit energy to be supplied over these wires to the traffic locking relays FR long enough to insure that the contacts of all of the relays will complete their movement from one position to the other. This insures that the equipment at all of the locations will be conditioned to change the established direction of trafiic. After the contacts of relays FR move from one position to the other they will remain in the position to which they have been moved even though the line circuit is interrupted and the supply of energy to the relays is cut oil.

Modification shown in Fig. 2

trance of a train into the single track stretch, the

pick-up and stick circuits for the associated directional stick relay ESR or WSR are interrupted and its contacts releaseand interrupt the circuit of line wires 20 and 2| with the result that the indication relays BPR at the ends of the line circuit release and extinguish the lamps M.

It may be preferred to have the equipment operate so that the lamps M will be lighted at all times when the single track stretch is vacant,

' and Fig. 2 shows how the system of Fig. 1 may be modified to prevent release of the relays WSR and ESR on movement of the associated control lever until a train enters the single track stretch.

Except for modification of the pick-up circuit for relay ESR by elimination of lever contact 93 therein, andthe addition of lever contact I 31 in the pick-up circuit of relay IPBSR, the equipmentis the same as that shown in Fig. 1, while it is to be understood that similar modifications are made in the equipment at the other end of the line circuit.

In operation, when eastbound traffic is established energy is suppliedfrom battery ILB t'o wires 20 and 2! over back contacts [6 and ll of relay" lPBSR and front contacts [8 and [9 of relay ESR as explained in connection with Fig. 1. When it is desiredto cause signal E8 to display a permissive indication to permit an eastbound train to enter the single track stretch,

lever contact interrupts one stick circuit for re- 1 lay ESE. At thistime relay ESR is maintained energized 'by current supplied over its pick-up circuitwhich includes front contact 94 of track relay 4TB. Accordingly, contacts is and 19 of relay ESR maintain the circuit of line wires 2B and 2| and energy from battery ILB supplied to line wires 20 and 2 I energizes relays BPR so that contact 40 of relay lBPR. maintains the circuit of the lamp I M, while the relay 3BPR, not shown,

, ity effective to maintain the established direcat the east end of the single track stretch maintains the circuit of the lamp 3M. The block indication lamps IM and 3M, therefore, remain lighted after movement of lever IK to its position R and indicate that the singletrack stretch is not occupied.

At this time lever contact I31 interrupts the pick-up circuit of relay IPBSR andprevents en ergizationof relay IPBSR if the push button IPB should be depressed while the lever (K is in its position R. This prevents interference with the established direction oftraffic after the lever K has been moved to the position R to cause signal 5E8 to display a permissive indication and authorize a train to enter the single track stretch.

When an eastbound train accepts signal 5E8 and enters section 4T the track relay 4TB. releases and its contact 94 interrupts the pick-up circuit for relay ESR so that relay ESR releasesandits contact 14 interrupts the stick circuits for the relay and thereby prevents picking up of the relay until section 4T is vacated. In addition, on

release of the relayESR its contacts 18 and I9 interrupt the circuit of line wires 20 and 2| and thus cut off the supply of energy over these wires to the block indication relays BPR with the result that they release and extinguish the indication lamps M to thereby indicate to the 0perators in the towers at both ends of the single track stretch that the stretch is occupied.

When the train vacates section 41 track relay. 4TH picks up and energy is supplied to relay ESR over front contact 94 of relay 4TH. 'Therelay ESR, therefore, picks up and its contacts 18 and iii are closed to permit energyto be supplied over wires 20 and 21 when sections 5T and GT are vacated. Acwrdingly, as soon as sections 5'! to this positionwhen energy was supplied over 1 thesame manner.

and BT are vacated energy frombattery iLB is supplied over the line wires 20 and 2t andpicks up the relays IBPR and 3BPR so that they establish the circuits of the lamps IM and 3M and ;cause these lamps to. be lighted to indicate to the operators at both ends of the track stretch that the stretch is again vacant. l

The modification shown in Fig. 2 operates in the same manner as that shown. in Fig. 1 during a reversal of the established direction of trafiic,

and when the stretch is conditioned for westbound traffic.

Modification shown in Fig. 3,

In Fig. 3 of the drawings there is shown means to modify the equipment at an end of the line circuit if" the block'indication relays ofthe system of Fig. 1 arenot required. The system shown in Fig. 3 is similar to that shown inFig. 1, but d ffers therefrom in that the block indication relays BPR and the lamps M are omitted, while the circuits for supplying to the line circuit at the entrance end of the stretch energy of the polartion of trafhc are also omitted, and a connection betweenthe line wires is substituted.

Only the equipment at the left-hand or west end of the stretch is shown in Fig. 3, but it is to be understood that the equipment at the rig ht-.

hand or east end of the stretch is modified The equipment of Fig. 3 is shown in thecondition which it assumes when the track stretch is conditioned for eastbound traflic,,the stretch is vacant, and lever lKis in its normal position N.

At this time the polar contacts of the tramc locking relays FR occupy their left-hand or normal positions so that control relays EFPR are energized and condition the stretch for eastbound traffic. The contacts of theserelays were moved the line circuit to establish eastbound traffic.

, After the direction of trafiie s established the 3 they then occupy. i

supply ofenergy to the line wires is cut off, but because of the operating characteristics of the relays their contacts remain in the position which The relay IPBSR is released and a connection between line wires 20 and M is established over back contacts 16 and ll of relay IPBSR. The

1 relay SPBSR, not shown, at the other end of the line circuit is also released so that connection is established between line wires 20 and 2| over its 1 back contacts.

If it is desired to permit an eastbound train to i enter the track stretch, the: lever [K is moved to its position R with theresult that contact 93 interrupts the pick-up circuit for relay ESR. and 3 contact l5 interrupts the stick circuit for relay ESE. Accordingly, the contacts of relay ESR release and contacts I8 and-l9 interrupt the line 1 wires 20 and 2| to prevent a change in the established direction of trafiic.

In addition, on thismovement of lever IK contact a establishes a circuit like that shown in Fig. 1, to 1 ,121??? arelay RHR to permit the display of a proceed indication by signal SES,

while when a train accepts this signal and enters section 4T the track relay 4'IR releases and its contact 94 interrupts thepick-up circuit of m y ESR, while its contact as interrupts the circuit of the signal control relaylFtHR and thus puts. g a 5 5 o te I When the v K, is return d to its ma position" and section AT is vacated energy is supplied to relay ESR over its pick-up circuit which includes lever contact 93 and front contact 94 of relay 4TB. Accordingly, relay .ES R picks up and its contact 14 establishes the stickcircuit for the relay, while its contacts l8 and 19 are closed to permit energy to be supplied over line wires 20 and 2|.

When it is desired to change'from eastbound to westbound trafiic the operator at the west end of the stretch can effect this change by depressing push button I PB, providing lever 5K is in its normal position, and the track stretch is vacant.

When the push button IPB is depressed energy is supplied to relay IPBSR over its .pick-up circuit which includes front contact ll] of relay IEFPR, push button IPB, and lever contact I31, while when relay IPBSR picks up its contact ll establishes a stick circuit including front contact In of relay IEFPR-to maintain itself energized after the push button is released. In addition, its contact l2 establishes a stick circuit for relay ESR to insure that its contacts I8 and 9 will remain picked up and maintain the circuit of the plied to the traffic locking relays FR in series and their contacts will be moved from their normal to the reverse positions with resultant release of the eastbound control relays EFPR and,

picking up of westbound control relays WFPR.

On release of relay IEFPR its contact Hi interrupts the stick circuit for relay IPBSR and its contacts l6 and I! cut off the supply of energy from battery ILB to wires 2!) and 2i and reestablish the connection between these wires. Because of the slow releasing characteristic of relay IEFPR, interruption of the stick circuit of relay lPBSR is delayed long enough to insure that energy will be supplied from battery ILB to wires 2%) and 2| for a period sufficient to insure that all of the traffic locking relays FR, will respond to the energyfrom battery lLB.

Contact I!) of relay lEFPR. also interrupts the pick-up circuit of relay lPBSR so that the contacts of relay IPBSR will remainreleased and will maintain the connection between line Wires 20 and 2| if the push button lPBshould be depressed when the single track stretch is conditioned for westbound traffic. i

In addition, on release of relay. IEFPR the circuit of relay RHR controlling signal 5E8 is interrupted, as is shown in Fig. 1, so that the signal BES governing entrance of eastbound trains into the ingle track stretch cannotbe caused to display a permissive indication when the single track stretch is conditioned for westbound trafiic.

On picking up of relay IWFPR its contact I92 establishes a stick circuit to maintain relay ESR energized when section 4T is occupied, or if lever IK is moved to its position R so that contacts I5 and 93 interrupt the circuits which they control for supplying energy to relay ESR. Accordingly, contacts l8 and [9 of relay ESR remain picked up and maintain the circuit of line wires 20 and 2| so that energy may .be'supplied over these line wires to change from westbound to eastbound traffic. 1

As a result of release of eastbound control relay EFPR and picking up of Westbound control relays WFPR the track circuit apparatus is connected to the rails of the track sections in the manner appropriate for westbound traific, while the equipment at the east end of-the stretch is conditioned to permit'the operator atthat point to cause the signal governing entranceof westbound trains into the track stretch to display 'a permissive indication.

The equipment operates in substantially the same manner on a change from westbound to eastbound trafiic and its operation need not be traced in detail. 1

Although, I have herein shown and described only one form of trafiic locking apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appendedclaims without departing from the spirit and scope of my invention.

Having thus described my invention, what'I claim is:

1. In combination, astretch of railway track extending between a first and a second location and over which traffic may move in either direction between said two locations, a first signal at saidfirst location governing entrance of trains into said track stretch, a second signal at said second location governing entrance of trains into said track stretch, a first polarized relay at said first location, means effective only when the contacts of said first polar relay are in their normal position to permit said first signal to provide a permissive indication, a second polar.- ized relay at said second location, means efiective only when the contacts of said second polarized relay are in' their reverse position to permit said second signal to provide a permissive indication, a line circuit over which said polarized relays may be energized in series, means at said first location for supplying energy of reverse polarity to said line'circuit, means at said second location for supplying energy of normal polarity to said line circuit, means effective only when the contacts of said first polarized relay are in their normal position to energize said polarized relays in series with energy of normal polarity supplied to said line circuit at said first location, and means efiective only when the contacts of said second polarized relay are in their reverse position-to energizesaid polarized relays in series with energy of reverse polarity supplied to said line circuit at said second location.

2. In combination, a stretch of railway track extending between a first and a second location and over which traffic may move in either direction between said two locations, a first signal at said first location governing entrance of trains into said track stretch, a second signa1 at said second location governing entrance of trains into said track stretch, a first polarized relay at said first location, means efiective only when the con tacts of said first polar relay are in their normal position to permit said first signal to provide a permissive indication, a second polarized relay at said second location, means efiective only when the contacts of said second polarized relay are in their reverse position to permit said second signal to provide a permissive indication, a line circuit over which said polarized relays may be energized in series, a first control-relay. at the first location effective when energized to. cause energy of reverse polarityto be supplied to said line circuit, a second controlrelay at the second location efiective when energized to cause energy of normal, polarity to besupplied to said line circuit, means for supplying energy to said first control relay provided the contacts of said first polarized relay are in their normalp'osition, and

means for supplying energy to said second control relay provided the contacts of said second polarized relay areiintheir reverse position.

3.,In combination, a stretch of railway track extending betweena first and a second location and over which trafi'ic may move in either direc- -tion between said two locations, a first signal at .said first location governing entrance of trains for supplying energy to said second control relay provided the contacts of said second polarized relay are in their reverse position.

5. In combination, a stretch of railway track extending between a first and a second location and over which traffic may mov in either direction between said two locations, a first signal at said first locationgoverning entrance of trains into said track stretch, a second signal at said second location governing entrance of trains into said track stretch, a first polarized relay at said first location, means efiective only when the contacts of said first polar relay are in their nor I mal position to permit said first signal to protion, a pair of line wires over which said polarized relaysmay be energized in series, means at said first location efiective when the contacts of said first polarized relay are in their reverse posiwires means at, said second location effective when the contacts of saidsecond polarized relay are in their normaluposition to establish connection between said line wires, means efiective only when the contacts of said first polarized relay are in their normal position to energize said polarized relays in series with energy of reverse polarity supplied to said line circuit at said first location, and means effective only when the contacts of, said second polarizedrelay are in their reverse position to energize said polarized relays in series with energy of normal polarity supplied to said line circuit at sa'idsecond location; 1

4. In combination, a stretch of railway track extending between a first and a second location and over which traffic may move in either directionbetween said two locations, a first signal at said firstlocation governing entrance of trains'into said track stretch, a second signal at said second location governing entrance of trains into said track stretch, a first polarized relay at said first location, means efiective only when the contacts of said first polar relay are in tion to establish connection between said line 3 vide a permissive indication, a second polarized relay at said second location, means efiective only when the contacts of said second polarized relay are in iiieir reverse position to permit said second signal to provide a permissive indication, a pair of line wires over which said polarized relays may b energized in series, a I

first control relay at said first location effective when released to establish connection I between said line wires and effective when energized to cause energy of reverse polarity to be supplied to said line Wires, a second control relay at said second location effectiv when released toes: tablish connection between said line wires and effective when energized to cause, energy of normal polarity to be supplied to said line wires,

a pick-up and a stick circuit for said first con trol relaygoverned by a normal polar contact of said first polarized relay, a pick-up and a stick circuit for said second control relay governed by a reverse polar contact of said second polarized relay, means for establishing the pick-up circuit for said first control relay, and means; for establishing the pick-up circuit for said second control relay.

, 6. In combination, a stretch ofqrailway track extending between a first and a second location and over which trafiic may move in either directheir normal position to permit said first signal to provide a permissive indication, asecond polarized relay at said second location, means effective only when the contacts of said: second polarizedrelay are in their reverse position to permit said second signal to provide a permissive indication, a pair of line wires over which said polarized relays may be energized in series, a first control relay at saidiirst location effective when released to establish connection between said line wires and effective when energized to cause energy of reverse polarity to be supplied to said line wires, a second control relay at said second locationefiective when released to establish connection between said line wires and effective when energized tocause energy of normal polarity to be supplied to said linewires, a circuit for supplying energy to said first control relay provided the contacts of said first polarized relay are in their normal position, and a circuit tionbetween said two locations, a first signal at said' first location governing entrance of trains into said track stretch, a second signal at said I second location governing entrance of trains into said track stretch, a first polarized relay at said first location, means effective only when the contacts of said firstpolar relay are in their normal position to .permit said first signal to provide a permissive indication, a secondpolarized relay at said second location, means effective only when the contacts of said second polarized relay are in their reverse position to permit said secondsignal to provide a permissive indication, a pair of line wires over which said polarized relays may be energized in series, a first control relay at said first location effective when released to establish connection between ,said line wires and effective when energized to to said line wires, a second control relay at said normal position, and means for establishing a second location effective when released to establish connection between said line wires andsaid first polarized relay are in their normal position, said first control relay when energized being effective to establish a stick circuit to maintain itself energized as long asthe contacts of said first polarized relay remain in their pick-up circuit for said, second control relay 1 nal at said first location governing entrance of trains into said track stretch, a second signal at said second location governing entrance of trains into said track stretch, a first polarized relay at said first location, means effective only when the contacts of said first polar relay are in their normal position to permit said first signal to provide a permissiv 'indication, a second polarized relay at said second location, means efiective'onlywhen the contacts of said second polarized relay are in their reverse position to permit said second signal to provid a permissive indication, a pair of line wires over which said polarized relays may be energized in series, a first control relay at said first location effective when picked up to cause energy of reverse polarity to be supplied to said line wires, said first control relay being efiective when released to establish connection between said line wires if, the contacts of said first polarized relay are in their reverse position and to cause energy ofnormal olarity to be supplied to said line wires if the contacts of said first polarized relay arein their normal position, a second control relay at said second location efiective when picked up to caus energy of normal polarity to be supplied to said line wires, said second control relay being effective when released to establish connection between said line wires if the contacts of said second polarized relay are in'their normal position and to causeenergy of reverse polarity to be supplied to said line wires if the contacts of said second polarized relay are in their reverse position, a circuit governed by a normal polar contact of said first polarlzed relay for supplying energy to said first control relay, and a circuit governed by a reverse polar contact of said second polarized relay for sup-' plying energy to said second control relay,

8. In combination, a stretch of railway track extending between a first and a second location and over, which traflic may move in either direction between said two locations, a first signal at said first location governing entrance of trains into said track stretch, a second signal at said second location governing entrance of trains into said track stretch, a first polarized relay at said first location, means elfective only when the contacts of said first polar relay are in their normal position to'permit said first signal to provide a permissive indication, a second polarized relay V first location, meansfefiective only when the contactsof said first polar relay are in their'normal position to permit said first signal to provide a provided the contacts of said second polarized "relay arein their reverse position, said second ized relay are in their normal position} a second control relay at said second location efiective when picked up to cause energy of normal polar contacts of said second polarized relay are in their normal position and to cause energy-of reverse polarity to be supplied to said line wires if the contacts of said second polarized relay are in their reverse position, means effective onlywhen the contacts of said first polarized relay are in their normal positions for supplying energy to said first control relay, and means efiective only when the contacts of said second polarized relay are in their reverse positions for supplying energy to said second control relay.

9. In combination, a stretch of railway track extending between a first and a second location and over which traffic may move in either direction between said two locations, a first signal at said first location governing entrance of trains into said track stretch, a second signal at said second location governing entrance of trainsinto said track stretch, a first polarized relay at said permissive indication, a second polarized relay at said second location,imeans eiTective only when the contacts of said second polarized relay are in their reverse position to permit said second signal to provide a permissive indication, a line circuit over which said polarized relays may be energized in series, a first indication relay at said first location and a second indication relay at said second location,

means at said first location for supplying energy of reverse polarity to said line circuit, and means at said second location for supplying energy of normal polarity to said line circuit.

10. In combination, a stretch of railway track extending between a first and a second location and over which trafficmay move in either direction between said two locations, a'first signal at said first location governing entrance of trains into said track stretch, a second signal at said sec- 0nd location governing entrance of trains into said track stretch, a first polarized relay at said first location, means effective only when the contacts of said first polar relay are in their normal position to permit said first signal to provide a permissive indication, a second polarized relay at said second location, means efiective only when at said second location, means effective only When cause energy of reverse polarity to be supplied to said line wires, said first control relay being effective when released to establish connection between said line wires if the contacts of said first polarized relay are in their reverse position and to cause energy of normal polarity to be supplied to said line wires if the contacts of said first polarthe contacts of,said second polarized relay are in their reverse position to permit said second signal to provide a permissive indication, a pair of line wires over which said polarized relays may be energized in series, a first control relay atsaid first location effective when picked up to cause energy of reverse polarity to be supplied to said line wires, said first control relay being efiective when released to establish connection between said line wires if the contacts of said first polarized relay are in their reverse position and to cause energy of normal polarity to be supplied to said line wires if the contacts of said first polarized relay are in their normal position, a second control relay at said second location effective when picked up to cause energy of normal polarity to besupplied to said line wires. said second control relay being effective whenjreleased to establish connectionbetween said line wires if the contacts of said each of said indication relays having its winding-connected in series with said -l1ne circuit and controlling an indication device,

second polarized relay are in their normal posi tion and to cause energy of reverse polarity tobe, supplied to said line wires if the contacts of said second polarized relay are in their reverse position, a first indication relay at said first location and a second indication relay at said secondlocation, each, of said indication: relays having its winding connected inseries with said line circuit and being responsive toenergy of either polarity supplied over said line circuit and controlling an indication device, means effective only when the contacts oi saidfirst polarized relayare in their normal position for supplying energy to said first control relay, means effective only when the contacts of said second polarized relay are intheir reverse position for supplying energy to said second control relay, and means governed by trafiic in said track stretch and controlling the circuit of said line wires.

11. In combination, a stretch of railway track extending between a first and a second location and over which traffic may move in either direction between said two locations, a first signal at said first location governing entrance of trains into said track stretch; a second signal at said second location governing entrance of trains into said track stretch, a first polarized relay at said said track stretch, a first polarized relay at said first location, a second, polarized relay at said second location, a pair of linewires governed by first location, means effective only when the contacts of said first polar relay are in their normal position to permit said first signal to provide a permissive indication, a second polarized relay at said second location, means effective only when the contacts of said second polarized relay are in their reverse position to permit said second signal I to provide a permissive indication, a pair of line wires governed by traffic in said track stretch and l over which said polarized relays may be energized in series, a first control relay at said first location effective when picked up to cause energy of reversepolarity to be supplied to said line wires, 1

said first control relay being effective wherrreleased to establish connection between said line 1 wires if the contacts of said first polarized relay are in their-reverse position and to cause energy of normal polarity to be supplied to said i line wires if the contacts of said first polarized relay are in their normal position, a second con trol relay at said second location effective when picked up to cause energy of normal polarity to be supplied tolsaid line wires, said second control relay being effective when released to establish connection between said line wires ifthe contacts of said second polarized relay are in their normal position andto cause energy of reverse polarity to be supplied to said line wires if the contacts of said second polarized relay are in their reverse position, a first auxiliary relay at said first location and a second auxiliary relay at said second location, each of said auxiliary relays having its winding connected in series with one of said line Wires, means for supplying energy to said first control relay provided the contacts of said first polarized relay are in their normal position and the contacts of said first auxiliary relay are picked up, and means for supplying en-.

ergy to said second control relay provided the contacts of said second polarized relayare in their reverse position and the contacts of said second auxiliaryrelay are picked up, a

12. In combination, a stretch of railway track into said track stretch, a second signal at said,

traffic in said track stretch and over which said tacts of said first polarized relayare in their normal position, means effective only when said first control member isin its second position and the contacts of said first polarized relay are in theirnormal position to permit said first signal to provide a permissive indication, a second control relay at said second location effective when picked up to cause energy of normal polarity to be supplied to said line wires, a second control member movable between a first and a second position, means for supplying energy to said second control relay providing said second control v member is in itsfirst position and the contacts of said second polarized relay are in their reverse position, and meanseifective only when saidsec- 1 0nd control member is in its second position and the contacts of said second-polarized relay are, in their reverse position to permit said second signal to provide a permissive indication. l w

13. In combination, a stretch of railway-track extending between afirst and a second location and over which traffic may move in either direction between said two locations, a first signal at said first location governing entrance of trains into said track stretch, a second signal at said second location governing entrance of trains into i said track stretch, a first polarizedrelay at said first location, a second polarized relay at said second location, a pair ofline wires governed by traific in said'trackstretch and over which said polarized relays may be energized in series, a

first control member movable between a first and a second position, means for supplying energy of ,reverse polarity to said line wires providing said first control member is in itsfirst position and the contacts of said first polarized relay are in their normal position, means efiective only when said first control member is in its second position and the contacts of said first polarized relay are in their normal position to permit said first signal-to provide a permissive indication, a second control member movable between a first and a second position, means for supplying energy'fof normal polarity to saidline wires providing said second control member is in its first position and the contacts of said second polarized relay are in their reverse position,and means effective only when said second control member is in its second position and the-contacts of said second polarized relay are in their reverse position to permit said secondsignal to provide a permissive indication,

14; In combination, a stretch of railway track extending between a first and a second. location and over which traffic may move in either direction between said two locations, a first signal at said first location, governing entrance of trains into said track stretch, a second signal at said second location governing entrance of trains into said track stretchga first polarized relay at said first location, a second polarized relay at said second location,a pair of line wires governed by trafiic in'said track stretch and over which said polarized relays may be energized in series, a first l control relay at said first location efiective when picked up to cause energy of reverse polarity to be supplied to said line wires, a first control member movable between a first and a second position, means for'supplying energy to said first control relay providing said first control member is in its first position and the contacts of said first polarized relay are in their normal position, a contact of said first control relay being effective whenpickedup to establish a stick circuit for the relay as long as-the contacts of said first polarized relay are-in their normal position, means efiective only when said" first control member is in its second position and the contacts of said first polarized relay are in their normal position to permit said first'signal to provide a permissive indication, a second control relay at said second location effective when picked up to cause energy of normal polarity to be supplied to said line wires, a second control member movable between a first and a second position, means for supplying energy to vsaidse'cond control relay providing said second control member is in its first position and the contacts of said second polarized relay are in their reverse position, a contact of said second control relay being effective when picked up to establish a stick circuit for the relay as long as th contacts of said second polarized relay are in their reverse position, and means effective only whensaid second control member is in its second position and the contacts of said second polarized relay are in their reverse position to permitsaid second signal to provide a permissive indication.

15. 'In combination, .a stretch of railway trackv extending between a first and a second location and over which trafi'ic may move in either direction between said two locations, a first signal at said first location governing entrance of trains into said-track stretch, a second signal at said sec'onol location governing entrance of trains into said track stretch, a first polarized relay at said first location, a second polarized relay at said second location, a pair of line wires governed by trafiic in said track stretch and over which said polarized relays may be energized in series, a first control relay at said first location effective when picked up to cause energy of reverse polarity to be supplied to said line wires, said first control relay being efiective when released to establish connection between said line wires if the contacts of said first polarized relay are in their reverse position and to cause energy of normal polarity to be supplied to said line wires if the contacts of said first polarized relay are in their. normal position,

a second control relay at said second location effective when picked up to cause energy of nor-- mal polarity to be supplied to said line wires, said second control relay being efiective when released to establish connection between said line wires if the contacts of said second polarized relay are in their normal position and to cause energy of refirst polarized relay are in their normal position and the contacts of said first auxiliary relay are picked up, means efiective only when saidfirst control member is in its second position and the contacts of said first polarized relay are in their normal position to permit said first signal to provide a permissive indication, means for supplying energy to said second control relay provided said second control member is in its first position, the

contacts of said second polarized relay are in their reverseposition and the contacts of said second auxiliary relay are picked up, and means effective only when said second control member is in its second position'and the contacts of said second polarized relay are in their reverse position to permit said second signal to provide a permissive indication.-

16. In combination, a stretch of railway track extending betweena first and a second location and over which trafilc may move in either direction betweensaid two locations, the rails of said track stretch being divided into a plurality of track sections each of which is provided with a track circuit for each direction of traflic, each of said track circuits comprising a source of energy a connected across the section rails at the exit end of the section and a track relay connected across the section rails at the entrance end of the section, a first polarized relay at the first location, a second polarized relay at the second location, and a polarized relay at each point of division between th track sections in said track stretch, a line circuit over which all of said polarized relays may be energized in series, the track circuit apparatus at each end of each track section being governed by the polarized relay at that end of the track sectionin such manner that the apparatus for the track circuits employed for traific movement from the first to the second location are connected with the section rails when and only when the polarized relay contacts occupy their normal position and so that the apparatus for the track circuits employed for traffic movements from the second to the first location are connected with the section rails when and only when the polarized relay contacts occupy their reverse position, a first signal at said first location governing entrance of trains into said track stretch, a second signal at said u 7 second location, governing entrance of trains into said track stretch, means at said first location for supplying energy of reverse polarity to said line circuit, means at said second location for supplying energy of normal polarity to said line circuit, means governed by the track relay at the adjacent end of the track section in ad ance of said first signal and effective only when the contacts of said first polarized relay are in their normal position to permit said first signal to provide a permissive indication, and means governed loy the track relay at the adjacent end of the track section in advance of said second signal and effective only when the gontacts of said second polarized relay are in their reverse position to permit said second signal to provide a permissive indication.

said first control relay provided said first control 17. In combination, a stretch of railway track it extending between a first and a second location and over which traific may move in either direction between said two locations, the rails of said track stretch being divided into a. plurality of track sections each of which is provided with a track circuit for each direction of traffic, each of said track circuits comprising a source of energy connected across the section rails at the exit end of the section and a track relay cona reverse position, a first signal at said first loca nected across the section rails at the entrance end of the section, a first polarized relay at the first location, a second polarized relay at the second location, and a polarized relay at each point of division between the track sections in said track stretch, the track circuit apparatus at each end of each track sectionbeing governed by the polarized relay at that end of the'track secwhenthe polarized relay contacts occupy their tion governing entrance of trains into said track stretch, a second signal at said second location governing entrance of trains into said track stretch, a line circuit controlled by the track circuit apparatus for said track sections and over which all of said polarized relays may be energized in series, means at said first location for supplying energy of reverse polarity to said line circuit, means at said second location for supplying ener y of normal polarity to saidline circuit, means eifective only when the contacts of said first polarized relay are in their normal position to permit said first signal to provide a permissive indication, and means effective only when the contacts of said second polarized .relay are in their reverse position to permit said sec ond signal to provide a permissive indication.

, CHARLES W. FAILOR. 

